Mandrel



A. w. CLAUDER.

MANDREL. APPLICATION FILED mmzo. I9I7.

Patented N 0v. 9, 1920.

61 twine 138 UNITED STATES PATENT OFFICE.

ARTHUR W. CLAUDER, OF BRIDGEPORT, CONNECTICUT, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO COLUMBIA GRAPHOPHONE MANUFACTURING COMPANY, OF BRIDGE PORT, CONNECTICUT, A CORPORATION OF DELAWARE.

MANDREL.

Specification of Letters Patent,

Application filed March 20, 1917. Serial No. 156,147.

To all whom it may concern:

Be'it known that I, ARTHUR W. CLAUDER, a citizen of the United States of America, and a resident of Bridgeport, Connecticut, have invented a new and useful Improvement in Mandrels, which invention is fully set forth in the following specification.

This invention relates to mandrels for sound-record tablets, and it has for an object to provide a mandrel of this type which is simple in construction, inexpensive to manufacture, and efficient inoperation.

It is customary to provide cylindrical sound-record tablets with a slightly tapered bore and to similarly taper the exterior surface of the mandrel. In the course of manufacture, however, slight variations occur in the mean diameter of both the bore of the tablet and the outer surface of the mandrel, and also in the degree of taper of both the tablet bore and the mandrel surface, whereby different tablets do not fit different mandrels with the same degree of accuracy. Again, tablets and mandrels are ordinarily made of different materials possessing different coefficients of expansion and contraction. It therefore becomes of importance that the mandrel be so constructed as to conform itself to the bores of different recordtablets, and that provision be made for the change in dimensions of the tablet bore and the mandrel surface under different temperature conditions. It is also of importance, particularly in machines employing correction devices wherein the record on the tablet is to be gaged by an arbitrary scale bearing a definite relation to the travel of the sound-box, that the sound-record tablet always assume a predetermined position with respect tothe mandrel without danger of breakage owing to variations in the dimensions of the tablet bore and the mandrel surface.

It is an object of this invention to provide a mandrel which shall permit the tablet to be predeterminately positioned without dan ger of breakage, and which shall compensate for variations in the dimensions of the tablet bore and the mandrel surface arising from any of the causes above enumerated.

A further object of this invention is to provide a mandrel for sound-record tablets with a tablet-engaging element which shall automatically adjust itself to difierent tapers of the bores of different tablets.

Described generally, the invention comprises a body or shell provided with a plurality of apertures, tablet-engaging elements mounted within said apertures for both inward-and-outward and for rocking movement, and resilient means normally urging said tablet-engaging elements outwardly.

Described with relation to the mandrel shaft, the invention comprises the provision of automatically expansible tablet supports which are arranged in two groups along the axis of the shaft, the members of each group being capable of changing their inclination to the axis of the shaft. Each group includes a minimum of three tablet-engaging members which are preferably maintained in definite relation to the shaft by means of a shall or body approximating the base of the ta et.

The invention is capable of receiving a variety of mechanical expressions, one of which is shown in the accompanying drawing, but it is to be expressly understood that the drawing is for purposes of illustration only, and is not to be construed as a definition of the limits of the invention, reference being had to the appended claims for that purpose.

Referring in detail to the drawing, wherein the same reference characters indicate corresponding parts in the several figures,

Figure 1 is a perspective of a mandrel embodying the present invention; and

Fig. 2' is a central longitudinal section thereof.

1 designates any conventional manldrel shaft upon which issupported in any suitable way, as by one or more disks 2, a cylindrical shell 3, which is shown as tapered in conformity with the usual practice. It will be understood, however, that the invention is capable of applicationto mandrel bodies which are neither tapered nor cylindrical on their outer surfaces. Said shell 3 is shown as provided with a plurality of longitudinally spaced apertures 4, preferably a plurality of pairs of longitudinally alined elongated slots, the slots of each pair being respectively positioned adjacent the opposite ends of the shell, and the slots at each end of the shell Preferably being equally spaced Patented Nov. 9, 1920.

circumferentially. Mounted within each of said apertures 4 is a tablet-engaging element, shown as a block 5 generally conforming in shape to that of the aperture but fittting the same loosely so as to be movable therein.

- short distance, one sixty-fourth of an inch each block is engaged by a spring 7.

florfiaxample, beyond the outer surface of the s e To resiliently urge the blocks 5 outwarg ly,

or convenience of manufacture, the springs are designed to engage longitudinally adjacent blocks and may be made integral and secured to the shell adjacent its central portion in any suitable way, as by a screw 8. Each block is also provided with a recess 9 in its inner face, and each spring 7 is provided with an outwardly bent end 10 for engagement in said recess 9. This arrangement prevents disengagement of. the spring and block, both when the block is urged outwardly to its extreme position and when the block is pressed inwardly. Preferably each recess 9 is of such depth and each spring end 10- of 'such length that, should a spring become disengaged from its corresponding block, it would engage the wall of the corresponding aperturefl and prevent rotation of the spring about its attaching means.

If desired, a tablet stop ring 11 may be provided on the mandrel shell and secured to the same in any suitable way, as by screws 12 passed through, inwardly turned tangs 13 formed integrally with said ring.

When the shell is supported between its ends by a disk 2, the latter will be suitably apertnr'ed, as shown at 14:, to admit of the passage therethrough of the'springs 7.

In operation, the tablet-engaging elements or blocks 5 are normally pressed outwardly by the springs 7 until the lips 6 engage the inner surface of the mandrel shell. When a tablet is'slipped onto the mandrel, the tablet-engaging elements 5 are moved inwardly in their apertures 4 against the tension of the springs 7 to admit of the tablet being moved into engagement with the stop ring 11. Said springs, however, urge said tablet-engaging elements outwardly in their apertures lnto' firm frictional engagement with the tablet bore and insure the rotation of the tablet with the mandrel. Furthermore, owing to the provision of the recesses 9 and the outwardly bent ends 10 of the springs 7,

each tablet-engaging "element 5 is tiltably mounted, as on aknife-edge, and can rock about the bent end 10 of its spring so as to conform itself'in inclination to the taper of ram/pee the tablet bore. This insures that each element contacts throughout its length with the tablet, although there be variations in the expressly understood that thesame is not to be restricted to the precise form shown on the drawing, as the invention may receive a variety of mechanical expressions, some of which willreadily suggest themselves to those skilled in the art. Moreover,'certain features thereof are capable of use without other features thereof. "Reference is therefore to be had to the claims hereto appended for a definition of the limits of this invention.

What is claimedis 1. A mandrel for sound-record tabletsprovided with a plurality of longitudinally spaced spring-pressed tiltable blocks normally projectlng through apertures therein.

2. A mandrel for sound-record tablets provided with a plurality of spring-pressed tiltable blocks normally projecting through apertures therein adjacent each end of said mandrel.

3. A mandrel for sound-record tablets provided adjacent each end witha plurality of apertures, tablet-engaging tiltable blocks mounted for movement in said apertures, and resilient means normally urging said tablet-engaging blocks outwardly.

4. A mandrel for sound-record tablets provided with longitudinally spaced apertures, tablet-engaging elements mounted for movement-in said apertures, resilient means normally urging said tablet-engaging ele ments outwardly, and means limiting the outward movement of said elements.

'5. A. mandrel for sound-record tablets provided with an aperture adjacent each end thereof, tablet-engaging elements mounted for movement in said apertures, means nor mally urging said tablet-engaging elements movement of said elements.

6. A mandrel for sound-record tablets provided with an aperture and a tiltable tablet-engaging element mounted for movement in said aperture.

. outwardly, and means limiting the outward 7. A mandrel for sound-record tablets provided with an aperture, a tablet-engaging element movable-therein, and means mounting said element for rocking movement. I

8. A mandrel for sound-record tablets provided with an aperture, and a tablet-engaging element mounted in. said aperture for inward-and outward and for movement.

9. A mandrel for sound-record tablets provided with an aperture, a tablet-engaging element mounted in said aperture for inward-and-outward and for rocking move:

rocking aeeaeee provided with a recess on its under face and said spring havingan outwardly bent end engaging in said recess.

12. A mandrel for sound-record tablets provided with longitudinally spaced apertures, tablet-engaging elements movable in said apertures, and means mounting said elements for rocking movement.

13. A mandrel for sound-record tablets provided with longitudinally spaced aperinally urging said elements outwardly, said last-named means engaging said elements with provision for rocking movement of said elements on said resilient means.

16. A mandrel for sound-record tablets provided with longitudinally spaced apertures, tablet-engaging elements movable in said apertures, each of said elements being provided with a recess in its inner face, and a spring attached to said mandrel at its central portion and provided with bent ends engaging in said recesses.

17. A mandrel for sound-record tablets provided with a plurality of apertures, tablet-engaging elements movable in said apertures, and means mounting said elements for rocking movement.

18.: A mandrel for sound-record tablets provided with a plurality of apertures, tablet-engaging elements movable in said apertures, and means mounting saidelements for inward-and-outward and for rocking movement.

19. A mandrel for sound-record tablets rovided with a plurality of apertures, tabet-engaging elements mounted in said apertures for inward-and-outward and. for rocking movement, and resilient means normally urging said elements outwardly.

20. A mandrel for sound-record tablets provided with a plurality of apertures, tablet-engaging elements movable in said apertures, and resilient means normally urging said elements outwardly, said last-named means engaging said elements with provision for rocking movement of said elements on said resilient means.

21. A mandrel for sound-record tablets provided adjacent each end with a plurality of apertures, tablet-engaging elements movable in said apertures, and means mounting said elements for rocking movement.

22. A mandrel for sound-record tablets provided adjacent each end with a plurality of apertures, tablet-engaging elements movable in said apertures, and means mounting said elements for inwardrand-eutward and for rocking movement.

23. A mandrel .for sound-record tablets provided adjacent each end with a plurality of apertures, tablet-engaging elements mounted in said apertures for inward-andoutward and for rocking movement, and resilient means normally urging said elements outwardly.

24. A mandrel for sound-record tablets provided adjacent each end with a plurality of apertures, tablet-engaging elements movable in said apertures, and resilient means normally urging said-elements outwardly, said'last-named means engaging said elements with provision for rocking movement of said elements on said resilient means.

25. In a sound-record tablet support, the i combination with a shaft, of an elongated spring extending longitudinally of the axis" of said shaft, means for supporting a por- -tion of saidspring between its terminals, in

fixed radial relation to the axis of said shaft,

ed on the terminals of said spring.

26. In a sound-tablet support,-the combiand tablet engaging means rockably' mountnation with. a shaft, of tablet-engaging members symmetrically arranged aboutthe axis of said shaft, bendable springs extending axially of the shaft and terminating centrally of said members, means for fulcruming said members on said springs, and means operatively securing he springs to said shaft.

In testimony whereof I have signed this specification. Y

ARTHUR w. CLAUDER. 

